Bring the steak to room temperature (15 minutes) and season it generously with 1 tsp kosher salt and 1/2 tsp freshly ground black pepper. Letting the meat warm briefly ensures even cooking; salt draws moisture to the surface then reabsorbs, improving flavor and forming a better crust when seared.

Prep the vegetables while the steak comes to temperature: core and halve the red and yellow bell peppers, remove seeds and membranes, then cut each half into 2–3 wide strips. Thinly slice the 1/4 red onion into half-moons and set aside. Slice the avocado in half, remove the pit, and cut into 6–8 slices; squeeze a few drops of lime over the flesh to keep it from browning. Prepping everything first lets you move quickly once the steak hits the heat so nothing overcooks.

Make the cilantro‑lime dressing: in a small blender or bowl, combine 2 tbsp packed cilantro, 1 garlic clove (peeled), juice of 1 lime (≈30 g), 1 tbsp olive oil, and a pinch of salt and pepper. Blitz until smooth and slightly emulsified. Taste and adjust—if it’s too tart, add a few drops of olive oil or a small pinch of sugar to balance. Blending the dressing emulsifies the oil into the citrus for a silky coating that clings to both steak and greens.

Heat a grill pan or heavy skillet over high heat until smoking-hot; this high heat is necessary to get a quick, caramelized sear on the skirt steak and to char the pepper flesh without overcooking the interior. Brush the steak lightly with 1 tsp olive oil to help conduct heat and prevent sticking.

Place the steak on the hot pan and sear 2–3 minutes per side for medium-rare (internal temperature about 130–135°F / 54–57°C). Skirt steak is thin and benefits from a fast, hot sear to develop deep flavor without becoming tough. If your steak is thicker or you prefer medium, add 1–2 minutes per side.

While the steak rests (very important—rest for 5–7 minutes under a loose tent of foil to allow juices to redistribute), put the pepper strips on the same hot pan cut-side down. Cook 2–3 minutes until blistered and charred in spots—this concentrates their sweetness and creates a smoky counterpoint to the beef. Turn once and cook another 1–2 minutes. Remove peppers and let cool slightly.

Slice the rested skirt steak thinly against the grain into 5 mm (about 1/4 inch) slices. Slicing against the grain shortens the muscle fibers and makes each bite tender. Arrange the mixed greens across two plates, scatter the blistered red and yellow pepper strips and sliced red onion, and fan the avocado slices on top.

Place the sliced steak over the salad, then drizzle the cilantro‑lime dressing over each plate (about half the dressing per plate), finishing with a few extra turns of freshly ground black pepper and a tiny pinch of flaky sea salt if desired. The warm steak will gently wilt the greens where it sits, marrying textures and temperatures for a composed dish.

Serve immediately, with lime wedges on the side. Encourage diners to toss gently to distribute the dressing and combine the creamy avocado with the tangy cilantro-lime vinaigrette for contrast with the charred beef.